Field of the Invention
The present invention relates to an image forming set, an image forming apparatus, and an image forming method.
Description of the Related Art
It has been known in an inkjet recording system that a post-treatment liquid is applied onto a surface of an image formed by jetting an aqueous ink in order to improve glossiness of the image.
The post-treatment liquid is applied after fixing the image formed by jetting the aqueous ink. There is also a case where the post-treatment liquid is applied onto a surface of an image in an unfixed state, after jetting the aqueous ink to form the image.
The post-treatment liquid includes ingredients, such as a resin, and wax. As the resin, or the wax form a uniform coating film on the surface of the image formed by jetting the aqueous ink, glossiness is imparted to the image. If the post-treatment liquid is applied onto a surface of an image formed by ejecting the aqueous ink in the unfixed state, however, the post-treatment liquid is mixed into the image. Therefore, a uniform coating film cannot be formed on the surface of the image, leading to a problem that glossiness of the image is poor. Note that, the unfixed state means a state where an image formed by ejecting an aqueous ink is not dried, and the image is not adhered to a recording medium.
To solve the aforementioned problem, proposed for the purpose of realizing high-speed printing is a recording material that, in which a difference between a solubility parameter (may be referred to as “SP value” hereinafter) of a water-soluble organic solvent in an ink and an SP value of a monomer component in ink-receiving particles having excellent ink adsorption is less than 5, and the SP value of the water-soluble organic solvent in the ink is 17.5 or less (for example, see Japanese Patent (JP-B) No. 4525778).
Moreover, disclosed is an ink set having excellent maintenance properties of an aqueous ink, in which water is contained in an amount of 50% by mass or greater relative to a total mass, and a solvent is contained in an amount of 5% by mass or greater relative to the total mass, and 50% by mass or greater of the solvent has the SP value of 27.5 (MPa)1/2 (13.4 (cal/cm3)1/2) or less (for example, see Japanese Patent (JP-B) No. 5398401).